1. Field of the Invention
The present invention relates to a procedure for feeding products in sheet form to a conveyor, in particular associated with an apparatus for packaging, and with a pick-up assembly in a sheet feeder that uses this procedure.
2. Discussion of the Background
In the field of the selection and transport products in sheet form, in particular in machines associated with packaging apparatus, there may be problems in correct and aligned feed of the products in sheet form, such as inserts, additional sheets, publishing products in general. In fact, these products usually require to be fed to a conveyor for collection and feed towards stations or machines for subsequent packaging and must be perfectly aligned over the underlying product.
In order not to create packaging problems and give the finished package, comprising the additional elements, a pleasing appearance, feed of single products in sheet form must be performed according to a direction well aligned and parallel to the one of the final position that must be obtained.
Moreover, it must be taken into account that to obtain a good grasp on the additional product it must e possible to grasp the product itself in an area with a certain amount of rigidity. This is also important in order for the product to be extracted without being broken and to avoid xe2x80x9ctearingxe2x80x9d of part of the product, which means it cannot be picked up by the suction cups.
Moreover, the current system for picking up and feeding the material in sheet form requires the transverse or longitudinal crease of the material in sheet form to be correctly aligned with the other publishing material to which it is to be added. Moreover, the insert or additional sheet must be correctly aligned with the pick-up area to enable it to be grasped correctly by the feeder or sheet feeder. For this purpose the feeder or sheet feeder is positioned laterally or astride the conveyor so that the insert can be grasped along the crease or the rigid area of this to be grasped correctly, as mentioned above.
The machine operator must then proceed, once the series of products and/or inserts to add on top of one another for subsequent packaging is known, to arrange the various sheet feeders according to the positions required depending on the crease of the particular insert and depending on the final position to be obtained in the package. This operation causes a loss of time to move the sheet feeder to the correct position.
The object of the present invention is to find a solution to these problems, by feeding products in sheet form towards a conveyor, in particular for example associated with a packaging apparatus, which generally consents feed of a generic insert, whatever the position (longitudinal or transverse) of its rigid or creased part.
This object according to the present invention is achieved by performing a procedure to feed products in sheet form to a conveyor, in particular associated with a packaging apparatus, and a pick-up assembly in a sheet feeder that uses this procedure, according to what is set down in the independent claims.
Other characteristics emerge from the subsequent appended claims.